The rainbow cube has 14 faces. Each face has 4 stickers. 7 of the faces are triangular, 7 are square. It's about the same size as a cuboctahedron but not the same thing at all.
The rainbow cube can come in 7-colour and 14-colour versions. The pieces only fit in one position, so it makes little difference to how you solve it.
Lovely-looking puzzle that it is, the rainbow cube is very easy to solve - more so than a pyraminx. You can work from one triangle to the opposite one without having to mess up anything that you solve and no difficult last layer.